org.apache.flink.contrib.streaming.state

Class RocksIteratorWrapper

java.lang.Object

org.apache.flink.contrib.streaming.state.RocksIteratorWrapper

All Implemented Interfaces:

Closeable, AutoCloseable, org.rocksdb.RocksIteratorInterface

Direct Known Subclasses:

RocksTransformingIteratorWrapper

public class RocksIteratorWrapper
extends Object
implements org.rocksdb.RocksIteratorInterface, Closeable

This class was originally a wrapper around RocksIterator to check the iterator status for all the methods mentioned to require this check in the wiki documentation: seek, next, seekToFirst, seekToLast, seekForPrev, and prev. At that time, this was required because the iterator may pass the blocks or files it had difficulties in reading (because of IO errors, data corruptions or other issues) and continue with the next available keys. The status flag may not be OK, even if the iterator is valid.

However, after 3810 was merged, the behaviour had changed. If the iterator is valid, the status() is guaranteed to be OK; If the iterator is not valid, there are two possibilities: 1) We have reached the end of the data. And in this case, status() is OK; 2) There is an error. In this case, status() is not OK; More information can be found here.

Constructor Summary

Constructors

Constructor and Description
RocksIteratorWrapper(org.rocksdb.RocksIterator iterator)

Method Summary

Modifier and Type	Method and Description
void	close()
boolean	isValid()
byte[]	key()
void	next()
void	prev()
void	refresh()
void	seek(byte[] target)
void	seek(ByteBuffer target)
void	seekForPrev(byte[] target)
void	seekForPrev(ByteBuffer target)
void	seekToFirst()
void	seekToLast()
void	status()
byte[]	value()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

RocksIteratorWrapper

public RocksIteratorWrapper(@Nonnull
                            org.rocksdb.RocksIterator iterator)

Method Detail

isValid

public boolean isValid()

Specified by:

isValid in interface org.rocksdb.RocksIteratorInterface

seekToFirst

public void seekToFirst()

Specified by:

seekToFirst in interface org.rocksdb.RocksIteratorInterface

seekToLast

public void seekToLast()

Specified by:

seekToLast in interface org.rocksdb.RocksIteratorInterface

seek

public void seek(byte[] target)

Specified by:

seek in interface org.rocksdb.RocksIteratorInterface

seekForPrev

public void seekForPrev(byte[] target)

Specified by:

seekForPrev in interface org.rocksdb.RocksIteratorInterface

seek

public void seek(ByteBuffer target)

Specified by:

seek in interface org.rocksdb.RocksIteratorInterface

seekForPrev

public void seekForPrev(ByteBuffer target)

Specified by:

seekForPrev in interface org.rocksdb.RocksIteratorInterface

next

public void next()

Specified by:

next in interface org.rocksdb.RocksIteratorInterface

prev

public void prev()

Specified by:

prev in interface org.rocksdb.RocksIteratorInterface

status

public void status()

Specified by:

status in interface org.rocksdb.RocksIteratorInterface

refresh

public void refresh()
             throws org.rocksdb.RocksDBException

Specified by:

refresh in interface org.rocksdb.RocksIteratorInterface

Throws:

org.rocksdb.RocksDBException

key

public byte[] key()

value

public byte[] value()

close

public void close()

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable